Using OR patterns in shell wildcards

Question

Contents of my dir are

$ ls -lrt
total 0
-rw-r--r-- 1 user1 admin 19 Oct  8 12:31 night.txt
-rw-r--r-- 1 user1 admin 19 Oct  8 12:31 noon.txt
-rw-r--r-- 1 user1 admin 38 Oct  8 12:31 day.txt

I would like to list out details of files that have a word in the filename as specified.

Example :

$ ls -lrt *day|night*
ls: *day: No such file or directory
bash: night.txt: command not found

Expected output

-rw-r--r-- 1 user1 admin 19 Oct  8 12:31 night.txt
-rw-r--r-- 1 user1 admin 38 Oct  8 12:31 day.txt

How to list out different files matching 2 different partterns, or in short how to use regex with ls, so that I could OR the filename parts.

Original scenarion, there are many file in the directory, have shortened the case for asking.

Answer 1

You don't even need extended globbing enabled to do what you want. This will work in bash:

ls {day*,night*}

Answer 2

There is no option in ls to filter on filename but in most of the shells there are globbing extension man bash /Pattern Matching

ksh

ls -lrtd -- *@(day|night)*

zsh

setopt extendedglob
ls -lrtd -- *(day|night)*

or:

setopt kshglob
ls -lrtd -- *@(day|night)*

bash

shopt -s extglob
ls -lrtd -- *@(day|night)*

In any of these three shells you can do this, but note that if one of the cases doesn't match any file, that pattern will be left unexpanded (e.g. *day* night1.txt othernight.txt if there is no file name containing day; see man bash /EXPANSION or /Brace Expansion specifically):

ls -lrtd -- *{day,night}*

In any shells you can do:

ls -lrtd -- *day* *night*

In zsh, if there's either no day or night file, the last two commands will fail; set the nonomatch or csh_null_glob option, or add (N) after each pattern to avoid this.

Answer 3

Shells do not uses regular expressions for argument expansion.

You can enable the extended pattern matching by

$ shopt -s extglob

and then

$ ls @(day|night).txt
day.txt   night.txt

See for example the Bash Reference Manual (Pattern Matching)

Answer 4

You can pipe ls with grep as below

aashutosh@ubuntu:/tmp$ ls -ltrh
total 0
-rw-rw-r-- 1 aashutsh user 0 May  9 02:55 noon.txt
-rw-rw-r-- 1 aashutsh user 0 May  9 02:55 night.txt
-rw-rw-r-- 1 aashutsh user 0 May  9 02:55 day.txt

aashutosh@ubuntu:/tmp$ ls -ltr | grep 'night\|day'
-rw-rw-r-- 1 aashutsh user 0 May  9 02:55 night.txt
-rw-rw-r-- 1 aashutsh user 0 May  9 02:55 day.txt